/usr/ is in libntrack-dev 016-1.2ubuntu2.
This file is owned by root:root, with mode 0o755.
..
/usr/include/ntrack/
/usr/include/ntrack/common/
/usr/share/
/usr/share/doc/
/usr/share/doc/libntrack-dev/
/usr/share/doc/libntrack-dev/copyright
/usr/lib/
/usr/lib/pkgconfig/
/usr/lib/pkgconfig/libntrack.pc
/usr/include/
/usr/include/ntrack/common/ntrackidpool.h
/usr/include/ntrack/common/ntrackmonitor.h
/usr/include/ntrack/common/ntrack.h
/usr/include/ntrack/common/ntrackutil.h
/usr/include/ntrack/common/ntrackcompare.h
/usr/include/ntrack/common/ntracklist.h
/usr/include/ntrack/common/ntrackmacros.h
/usr/include/ntrack/common/ntrackbase.h
/usr/share/doc/libntrack-dev/README.gz
/usr/share/doc/libntrack-dev/NEWS.gz
/usr/share/doc/libntrack-dev/AUTHORS
/usr/share/doc/libntrack-dev/changelog.Debian.gz
/usr/lib/libntrack.so